The correct answer is: E. No Error
The sentence is grammatically correct and conveys the intended meaning. The word “told” is a verb that means to communicate something to someone. The word “him” is a pronoun that refers to the person who is being told the story. The word “story” is a noun that refers to the narrative that is being told. The word “in details” is an adverbial phrase that modifies the verb “told” and indicates that the story was told in a detailed manner. The word “to make him understand it fully” is an infinitive phrase that modifies the verb “told” and indicates that the purpose of telling the story was to make the listener understand it fully.
The other options are incorrect because they do not make sense in the context of the sentence. The word “I” is a pronoun that refers to the speaker, but it is not necessary in this sentence because the subject is already clear from the context. The word “the” is an article that is used to introduce a noun, but it is not necessary in this sentence because the noun “story” is already known. The word “was” is a verb that is used to indicate the past tense, but it is not necessary in this sentence because the tense is already clear from the context.